Strap cutter



H. T. MARTIN STRAP CUTTER Dec. 11, 1956 2 Sheets-Sheet 1 Filed Feb. 28,1955 INVENTOR.

44g WW V 6 11.4 n??? Ann r n 1 H. T. MARTIN Deb. 11, 1956 STRAP CUTTER 2Sheets-Sheet 2 Filed Feb. 28, 1955 INVENTOR.

United States Patent STRAP CUTTER Hollinshead T. Martin, Evanst on,111., assignor to Signode Steel Strapping Company, Chicago, 111., acorporation of Delaware Application February 28, 1955, Serial No.490,733

9 Claims. (Cl. 30-194) The present invention relates to a new andimproved manually operable cutter for severing the strap secured aroundor encircling bundles, bales, boxes, coils, packages and the like.

Many types of strap cutters have been proposed, and some of these havebeen marketed with considerable success. Most of them incorporate a pairof relatively movable shearing blades, usually pivoted together, withthe blades having shearing edges which move past each other to sever thestrap. Such shearing blades are necessarily heavy or thick in sectionand it is extremely diflicult, if not impossible, to insert them betweenthe bundle and a tightly tensioned encircling strap. This isparticularly true of straps binding the annulus of a coil of wire andthe like.

The strap cutter of the present invention is well adapted to cut highlytensioned strap which closely encircles a bundle and even coils of wireor tubing, and it is equally effective in cutting the strap when thereis little or no tension applied thereto.

It is, therefore, a principal object of the present invention to providea new and improved strap cutter wherein the cutting elements may beeasily applied to both highly tensioned strapping closely encircling abundle and to strapping which is under little or no tension.

Another object is to provide a new and improved cutting tool including apair of cutting elements, whose action is substantially transverse asrespects the strapping to enable the elements to be placed between thestrapping and a closely encircled bundle.

Another object is to provide a new and improved strap cutter wherein thecutter elements which are placed between the strap and the bundle barelyproject therebetween to minimize the possibility of damaging the bundle.

Another object is to provide a new and improved strap cutter having aplurality of cutting elements, two of which are adapted to be pivotedtoward and away from each other and the third of which is locatedbetween the first two and moves rectilinearly in the tool.

Other objects and advantages will become apparent from the followingdescription taken in conjunction with the accompanying drawings,wherein:

Fig. 1 is a perspective view of the head of the cutting tool, formingthe subject matter of the present invention, shown part way through acutting stroke;

Fig. 2 is an elevational view of the working elements of the cuttingtool in closed position and may be considered as being takensubstantially along the line 22 of Fig. 6 looking in the direction ofthe arrows;

Fig. 3 is a view similar to Fig. 2 but showing the tool in open positionto receive the strap to be severed;

Fig. 4 is a cross sectional view taken substantially along the line 4-4of Fig. 6 looking in the direction of the arrows;

Fig. 5 is a view similar to Fig. 4 but showing the tool in openposition;

Fig. 6 is a side elevational view;

Fig. 7 is a medial sectional view and may be considered 2,773,307Patented Dec. 11, 1956 as being taken substantially along the line 77 ofFig. 2 looking in the direction of the arrows; and

Fig. 8 is an end elevational view showing the tool in open or strapreceiving position.

Referring to the drawings, the tool is indicated as having a head 10including a pair of transversely spaced face plates 12 and 14 which areheld together by a pivot bolt 16 and nut 18 which project throughaligned holes 20 in the plates 12 and 14. The cutting elements of thetool are actuated by a pair of handles 22 and 24, the lower or outerportions of which are not shown, to conserve space in the drawings, butwhich may be of any conventional construction. The handles 22 and 24 areprovided with complementarily shaped and offset apertured ears 26 whichoverlap at those ends of the tool handles projecting between the plates12 and 14, and through which extends a pivot pin 28 the outer ends ofwhich are guided in grooves 30 formed in the inner faces of the plates12 and 14.

A pair of identical, fiat, and relatively thin cutters 32, havingapertured hub portions 33, are oppositely pivotally mounted between theplates 12 and 14 onthe pivot bolt 16. Each of the cutters 32 is adaptedto be rocked toward and away from the other and is provided with acutting edge 34 formed on a hooked jaw portion 56 thereof which isadapted to extend above top edges 38 of the plates 12 and 14. The hookedends 36 form with the hub portions 34 recesses 37 to accommodate thestrap S being cut as seen in Fig. l. The cutters 32 have only rockingmovements and each are formed with ears 40 which are apertured at 42 toreceive a pivotal connecting pin 44 which extends through an aperturedcar 46 on one of the handles 22 or 24 in accordance with which side ofthe bolt 16 the cutter 32 is mounted. The ends of the pins 44 slide onthe inner faces of the plates 12 and 14 and are there retained againstfalling free. The cutters are so arranged that when the handles arebrought together to the posi tion shown, for example in Figs. 2 and 4,the hooked ends 36 of the cutters are rocked toward each other and theirtips 48, being offset, will overlap as shown in Fig. 2.

It will be observed from Figs. 1, 6 and 8 that the cutters 32 have theirinner or adjacent faces spaced slightly apart to accommodatetherebetween a rectilinearly movable cutter plate or blade 50 providedwith a central slot 52 to permit movement thereof relative to the pivotbolt 16 and with arcuate cutting edges 54 at its upper or outer sidewhich meet at the center of the plate 50 in a wide V shape. At eitherside of the slot 52 the plate 50 is apertured at 56 to receive a pin 58which links it to one of the cutters 32, the pins 58 passing throughsuitable apertures in the cutters 32 and having a rather snug fittherewith and being retained against axial movement by the face plates12 and 14. Since the pins 58 will move in an arcuate path about the axisof the pivot bolt 16, the apertures 56 are somewhat larger than the pins58 to accommodate such arcuate movement. This is shown most clearly inFigs. 4 and 5. Consequently, as the handles are actuated to rock thecutters 32 about the pivot bolt 16 the pins 58 carry the cutter plate 50rectilinearly outwardly or inwardly of the tool head between the cutters32, and the cutting edges 54 cooperate and coact with the cutting edges34 to shear the straps in the manner illustrated in Fig. l.

A pair of L-shaped links 60 are arranged generally parallel to thecutters 32, and'each has a first arm 62 pivoted by means of an aperture64 to the pivot bolt 16 and a second and offset arm 66 formed with anaperture 68 to receive the pivot pin 44, thus connecting it to one orthe other of the operating handles 22 and 24. It will be observed fromFigs. 6 and 7 that the arms 62 lie adjacent the inner face of one or theother of the face plates 12 and 14, while the ofiset arms 66 lie to theinside of the handle cars 26. At their junctures the arms 66 and 62 areprovided with an aperture 70 snugly to receive the linking pin 58, tyingthe cutter plate 50 to the cutter 32. Consequently, the support for thelink 60 is insured and a positive drive is effected between theoperating handles 22 and 2a and the cutter blade or plate 50 so that itmoves forwardly or outwardly during the shearing stroke.

The shearing or severing action of this tool is shown in part in Fig. 1,which may be considered as looking at the strap from the bundle sidethereof. After the strap 5 has been engaged between the jaws 36 of thecutters 32 and across the top edges 38 of the plates 12 and 14, thehandles 22 and 24 are brought together. This movement rocks the cutters32 so that their tips 48 move toward each other on substantially astraight line. At the same time the cutter plate 50 moves outwardly sothat its cutting edges 54 move toward and across the cutting edges 34 ofthe cutters 32. As the strap S is confined among the three movablecutting elements, a pair of cuts C are made in the strap inwardly fromthe edges of and transversely across the strap by the two cutting edges34 of the cutters 32 and the two cutting edges 54 on the plate or blade50. Because the tips 48 of the cutters 32 are offset and overlap, asshown in Figs. 1 and 2, a short piece or bridge of metal B is leftbetween the cuts C shown in dotted lines, Fig. 1. This bridge of metal Bis as wide as the thickness of the cutter plate 50. When a highlytensioned strap is severed in this fashion, the tensional forces will besufiicient to break this metal bridge and, therefore, the severing ofthe strap will have been complete. On the other hand, if the strap isnot under high tension, or is under no tension whatsoever, it will beloose about the package. Then a slight twisting motion in the plane ofthe strap imparted to the cutter before it is opened or removed willvery easily break or tear the bridge portion B.

It will be observed from Figs. 2 to 5 that the movements of the tips 48of the cutters 32 are substantially toward each other. Since thesecutters are formed from relatively thin flat plate and have shallowhooked ends 36 and bevelled tips 48, they will enter into a very closespace between the strapping and the bundle or package which has beenbound. This means that a strapping which is very highly tensioned abouta package can be severed with no damage to the package and with thegreatest facility. This tool has been particularly effective in severingthe strapping placed about the annulus of a coil of wire or tubing,because the thin hooked ends can be entered between wire or tubingconvolutions to engage about the strapping.

It will be seen from the foregoing description that the objectives whichwere claimed for this invention at the outset of this description havebeen fully attained.

While a preferred embodiment of the strap cutting tool constituting thisinventionhas been shown and described, it will be apparent thatmodifications and variations thereof may be made without departing fromthe underlying principles of the invention. It is, therefore, desired bythe following claims to include within the scope of the invention allsuch variations and modifications by which substantially the results ofthis invention may be obtained by the use of substantially the same orequivalent means.

What is claimed as new and desired to be secured by United StatesLetters Patent is:

1. A strap cutter including in combination, oppositely rockableplate-like cutting elements having spaced inner faces and cutting edges,a third plate-like cutting element arranged in the space between saidfirst named cutting elements and slidable rectilinearly across and incontact withsaid spaced inner faces, said third cutting element havingcutting edges cooperable with and movable past said cutting edges onsaid'first named elements, and operable means connected to all saidcutting elements for actuating the same, whereby movement of all saidcut ting edges in strap cutting direction will shear the strap inparallel and overlapping cuts ofiset a distance equal to the thicknessof said third cutting element.

2. A strap cutter including in combination, oppositely rockableplate-like cutting elements having spaced inner faces and oppositelydisposed hooked ends on which are formed cutting edges, the hooked endsof said cutting elements being overlapped at the end of a cuttingmovement, a third plate-like cutting element arranged in the spacebetween said first named cutting elements and slidable rectilinearlyacross and in contact with said spaced inner faces, said third cuttingelement having cutting edges cooperable with and movable past saidcutting edges on said first named elements, and operable means connectedto all said cutting elements for actuating the same, whereby movement ofall of said cutting edges in strap cutting direction will shear thestrap in parallel and overlapping cuts oflset a distance equal to thethickness of said third cutting element.

3. A strap cutter including in combination, oppositely rockableplate-like cutting elements pivotally mounted on a common axis andhaving spaced inner faces and oppositely disposed hooked ends on whichare formed cutting edges and which when moved through a cutting strokehave their hooked ends overlapped, a third platelike cutting elementarranged in the space between said first named cutting elements andslidable rectilinearly across and in contact with said spaced innerfaces, means connecting said third element to said first named elementsfor movement in synchronism therewith, said third cutting element havingcutting edges cooperable with and movable past said cutting edges onsaid first named ele ments when said first named elements are rockedtoward each other, and operable means connected to said first namedelements for actuating the same, whereby movement of all of said cuttingedges in strap cutting direction will shear the strap in parallel andoverlapping cuts oifset a distance equal to the thickness of said thirdcutting element.

4. A strap cutter including in combination, a pivot pin, a pair ofoppositely rotatable spaced cutters pivotally mounted on said pivot pin,a rectilinearly movable cutter blade positioned in thespace between saidcutters, said cutters and said blade having cooperable shearing edges,means connecting said cutter blade to said pivotally mounted cutters sothat when said cutters are pivoted toward and away from each other saidcutter blade is moved rectilinearly, a pair of pivotally interconnectedhandles, and means operatively connecting said handles to said pivotallymounted cutters and said rectilinearly movable cutter blade.

5. A strap cutter including in combination, a pair of spaced parallelface plates, a pivot bolt extending through said plates, a pair ofoppositely rotatable axially spaced cutters pivotally mounted on saidpivot bolt, a rectilinearly movable cutter blade positioned in the spacebetween said cutters, said cutters and said blade having cooperableshearing edges, the shearing edges on said rotatable cutters havingtheir outer ends overlapped at the end of the cutting movement, meansconnecting said cutter blade to said pivotally mounted cutters so thatwhen said cutters are pivoted toward and away from each other saidcutter blade is moved rectilinearly, a pair of pivotally interconnectedhandles, and means pivotally connecting each handle to one of saidpivotally mounted cutters, whereby movement of said rotatable cutterssaid cutter blade in said cutting direction will shear the :strap inparallel and overlapping cuts offset a distance equal to the thicknessof said cutter blade.

6. A strap cutter comprising in combination, a pivot pin, a pair ofoppositely rotatable spaced cutters pivotally mounted on said pivot pin,a rectilinearly movable cutter blade positioned in the space betweensaid cutters, said cutters and said blade having cooperable shearingedges, linking pins connecting said cutter blade to said pivotallymounted cutters so that when said cutters are pivoted toward and awayfrom each other said cutter blade is moved rectilinearly, a pair ofpivotally interconnected handles, means pivotally connecting each handleto one of said pivotally mounted cutters, and a link pivotally connectedto each handle, to said pivot pin, and to one of said linking pins.

7. A strap cutter comprising in combination, a pivot pin, a pair ofoppositely rotatable spaced cutters pivotally mounted on said pivot pin,a rectilinearly movable cutter blade positioned in the space betweensaid cutters, said cutters and said blade having cooperable shearingedges, means connecting said cutter blade to said pivotally mountedcutters so that when said cutters are pivoted toward and away from eachother said cutter blade is moved rectilinearly, a pair of pivotallyinterconnected handles, means pivotally connecting each handle to one ofsaid pivotally mounted cutters, and additional means connecting saidhandles to said means connecting said cutter blade to said pivotallymounted cutters.

8. A strap cutter comprising in combination, a pair of spaced parallelface plates, a single pivot retaining bolt extending through saidplates, a pair of oppositely rotatable axially spaced cutters pivotallymounted on said pivot bolt and having hooked ends which overlap at theend of a cutting movement, a rectilinearly movable cutter bladepositioned in the space between said cutters and slidable across theinner faces thereof, said cutters and said blade having cooperableshearing edges, means connecting said cutter blade to said pivotallymounted cutters so that when said cutters are pivoted toward and awayfrom each other said cutter blade is moved rectilinearly, a pair ofhandles, a pivot pin interconnecting said handles, means on the innerfaces of said face plates for guiding said pivot pin for movement in thesame direction as said cutter blade, and means pivotally connecting eachhandle to one of said pivotally mounted cutters, whereby movement ofsaid rotatable cutters and said cutter blade in strap cutting directionwill shear the strap in parallel and overlapping cuts offset a distanceequal to the thickness of said cutter blade.

9. A strap cutter comprising in combination, a pair of spaced parallelface plates, a combination pivot and retaining bolt extending throughsaid plates, a pair of oppositely rotatable spaced cutters pivotallymounted on said pivot pin, a rectilinearly movable cutter bladepositioned in the space between said cutters, said cutters and saidblade having cooperable shearing edges, linking pins connecting saidcutter blade to said pivotally mounted cutters so that when said cuttersare pivoted toward and away from each other said cutter blade is movedrectilinearly, a pair of handles, a pivot pin interconnecting saidhandles, means on the inner faces of said face plates for guiding saidlast named pivot pin for movement in the same direction as said cutterblade, means pivotally connecting each handle to one of said pivotallymounted cutters, and a link pivotally connected to each handle, to saidpivot bolt, and to one of said linking pins.

References Cited in the file of this patent UNITED STATES PATENTS1,290,707 Brooks Jan. 7, 1919 1,356,882 Pendleton Oct. 26, 19201,901,903 Edwards Mar. 21, 1933 1,920,413 McGary Aug. 1, 1933

